1. Body Condition Score and Breeding Back
Steven E. Myers, Ph.D. Technical Sales Specialist Purina Animal Nutrition Edmond, OK

2. Body Condition Score 3
Very thin, no fat on the ribs or brisket, and some muscle still visible. Backbone is easily visible.

3. Body Condition Score 4
Thin, with ribs easily visible but shoulders and hindquarters still showing fair muscling. Backbone is visible.

4. Body Condition Score 4

5. Body Condition Score 5
Target at Weaning!
Moderate to thin. Last two or three ribs can be seen. Little evidence of fat in the brisket, over the ribs or around tailhead.

6. Body Condition Score 6
Target at Calving!
Good smooth appearance throughout. Some fat deposition in the brisket and over the tailhead. Ribs are covered and the back appears rounded.

7. Body Condition Score 6

10. Effect of BCS at Parturition on Postpartum Interval (PPI)
PPI (DAYS)
88.5
4.5
69.7
5.0
59.4
51.7
6.5
30.6
* Body Condition Scores have been converted to the 1-9 scoring system.
(Houghton, et al., 1990)

11. Reproductive Performance of First Calf Heifers Dependent upon BCS at Calving
Pregnancy Rate, %
Days to Pregnancy 4
64.9 92 5
71.4 82 6
87.0 74 7
90.7 76
(Coombs et al., 1996)

12. Evaluate in more detail…
Effect of Body Condition Score on:
Neonatal health
Pre-weaning performance
Post-weaning performance
Reproductive performance
Is it BCS or strategic supplementation during gestation (or both)?

13. Neonatal Period The calf is born “naïve” to pathogens
Immune system functional at 2 months of age
Colostrum
Provides for ingestion of immunoglobulins
Means of providing passive immunity
22% solids in colostrum vs. 12% in whole milk
2 quarts within 6 hours; 4 quarts within 12 hours
Concentration of immunoglobulins in colostrum begins 5 weeks pre-partum

14. Heifers’ Condition Score
Effects of Body Condition at Calving on Calf Vigor and Calf Serum Immunoglobulin Concentrations
Heifers’ Condition Score 2 3 4 5 6
P =
Interval from calving to standing for the calf (min) --
59.9
63.6
43.3
35.0
.24
Colostrum prod., ml
750.0
1525.0
1111.5
1410.9
.19
Calf Serum IgG1 (mg/dl)
1787.6
1998.1
2178.8
2309.8
2348.9
.23
Calf Serum IgM (mg/dl)
159.5
145.9
157.2
193.1
304.1
.05
(Odde et al., 1986)

15. Effect of Condition of the Cow on Calf Serum Concentrations
Cows’ Condition Score 3 4 5 6 7
P =
Calf Serum IgG1 (mg/dl)
1020.6
1360.8
1349.4
1485.3
1554.1
.19
Calf Serum IgM (mg/dl)
106.8
103.0
129.2
123.3
128.9
.55
(Odde, 1988)

16. Nutrition & Perinatal Immunity/Health
Calf serum IG levels improved when 1st calf heifers were in moderate BCS.
Less of an effect in older cows?
Increased calving difficulty significantly reduced calf serum IG levels (Odde et al., 1986)
Calf serum IG levels positively correlated with calf weights at 60, 180, and 240 days of age (Odde et al., 1986).
Calves born to heifers fed protein-restricted diets required more time to stand and produced 11% less body heat (Carstens et al., 1987).

17. Effects of Prepartum Nutrition on Calving Difficulty and Calf Performance*
Item
High a
Low b
P <
Heifer wt change, lbs
79.4
-12.8
.05
Birth weight, lbs
67.3
62.9
Assisted births, % 27 28
Calves alive at birth, % 97 90
Calf weaning wt, lbs
353
325
*First-calf heifers
a 100% of the recommended level of prepartum energy
b 65% of the recommended level of prepartum energy
(Corah et al., 1975)

18. Effects of Gestation Nutrition on Calving Difficulty and Calf Performance a
Item
Low
High b
Calf birth weight, lbs 63 69
Dystocia, % 35 28
Calf Survival, %
At Birth 93 91
At Weaning 58 85
Scours, %
Incidence 52 33
Mortality 19
Dam Pregnancy Rate, % 65 75
a Averages from 7 studies; cows and heifers combined.
b Diet level fed from up to 150 days precalving.
(Bellows, 1993)

19. Heifer Nutrition & Dystocia
Final Word:
“Reducing the birth weights of calves from first calf heifers by nutritional restrictions does not decrease the incidence of calving difficulty but greatly reduces postpartum reproductive performance.”
Dr. Robert Wetteman, Oklahoma State University
1993 Range Beef Cow Symposium

20. Effect of Cow BCS on Calf Performance
How/when is the restriction or gain program imposed? 6 4 3 7 6 4

21. Pre- and Postpartum Energy Combinations
Effects of Pre- and Postpartum Energy Intake on Calf Weaning Weight and Reproductive Performance
Pre- and Postpartum Energy Combinations
Item
LE-LEa
LE-HEa
ME-LEa
ME-HEa
205-d calf wt, lbs
409b
455bc
444bc
482c
PPI, days
72.6b
54.3c
65.7b
68.4b
In estrus w/in 60 days, %
33.3b
56.3c
52.9bc
54.3bc
a Prepartum nutrition program imposed on day 190 of gestation. Postpartum
nutrition program imposed for 60 days. LE = 70% NRC, ME = 100% NRC,
HE = 130% NRC.
(Houghton et al., 1990)

22. Effects of low or moderate nutrition1 of dams during 32 to 115 d of gestation on Body Weight and BCS
Treatment
Item
55% NRC1
>100% NRC1
P-value
Number 7
Day 32 BW, lbs
849
803
.31
Day 103 BW, lbs
792
924
.01
Day 262 BW, lbs
1100
1124
.63
Day 262 BCS
4.9
5.2
.04
Calf Results:
Prenatal nutritional treatment did not affect weaning weight,
ADG from birth to weaning, or 15 month weight of calves.
(Long et al., 2010)

23. Effect of Restricting Energy During the 2nd Trimester on Cow & Calf Performance
Item
BCS 4
BCS 6
P-value
Third trimester BCS
4.3
5.4
Parturition BCS 4 6
.001
Cow BW change, lbs (to day 60 PP)
-13
-23
.09
Milk production, lbs
18.9
19.3
.71
Calf birth weight, lbs
89.5
90.2
.83
Calf ADG, lbs (to day 60 PP)
1.91
2.00
.48
Average calf weight, lbs
168
177
First-service conception, %
36.1
50.0
.22
Overall pregnancy, %
63.9
88.9
.01
Cows were targeted to BCS 4 or 6 during the second trimester. Nutritional
adjustments continued in the third trimester.
(Lake et al., 2005)

24. Effects of Late Gestation Energy Level Fed to 1st Calf Heifers
Item
100% NRC
65% NRC
Calves alive at birth, % 97 90
Birth weight, lbs
67a
63b
Weaning weight, lbs
353a
324b
Milk production, lbs/day
10.6
11.0
Percent showing estrus 40 days PP 41 26
Age at puberty of F1 heifer calves, days
318
337
Energy level changes imposed on day 180 of gestation.
(Corah et al., 1975)

25. Effects of Late Gestation Energy Level Fed to 2nd Calf Cows
Item
High
Low
Calves alive at birth, %
100 90
Birth weight, lbs
77a
59b
Calves alive at weaning, % 71
Weaning weight, lbs
320a
294b
Milk production, lbs/day
12.1a
9.0b
Percent showing estrus by 40 days PP 48 38
Energy level restricted to both sets of cows on day At day
250, High cows were fed 19.3 Mcal DE versus 8.4 Mcal DE for the
Low cows. Both groups were fed 28.8 Mcal DE after calving.
(Corah et al., 1975)

26. Effect of BCS of Mature Cows on Cow & Calf Performance
Cow Body Condition Score
Item 4 5 6
Calf birth weight, lbs
63.6a
66.9b
71.3c
Dystocia score
1.2
Adjusted 205 day calf weight, lbs
411
425
436
Percentage of cows pregnant, 60-d
56a
80b
96b
Nutritional management to achieve BCS 4, 5, or 6 occurred 90 days prior
to parturition.
(Spitzer et al., 1995)

27. Effect of Postpartum Cow Weight Gain on Calf Weaning Weight
Targeted Postpartum Cow Gain
Item
1.0 lbs/day
2.0 lbs/day
Adjusted 205 day calf weight, lbs
414a
433b
Percentage of cows pregnant, 60-d
70a
84b
(Spitzer et al., 1995)

28. Milk Production, lbs/4 hours
Calf ADG and Milk Production of Brahman Cows Losing or Maintaining Body Condition/Weight From Calving to 50 Days Postpartum
Group
Calf ADG, lbs
Milk Production, lbs/4 hours
Cows losing weight (- 88 lbs postpartum)
1.91a
2.42a
Cows maintaining weight (+16 lbs postpartum)
2.31b
2.95b
(Bastidas et al., 1990)

29. Summary Points
Limited data imply that energy restriction to cows in 1st/2nd period has minimal effects on calf birth weight or weaning weight.
Late gestational energy restriction resulting in BCS 4 cows compared to BCS 6 cows:
Reduces birth weight, but with no effect on dystocia
Tends to reduce weaning weights
Reduces rebreeding performance
Milk production seems dependent on late gestation and early postpartum energy levels rather than BCS at parturition.
What about late gestational supplementation on post-weaning calf performance independent of BCS?

30. Effect of Late Gestation Supplementation on Performance of Heifer Progeny
3-year study with heifers born from dams who received the nutritional treatments.
Half of the cows received 1 lb/d of a 42% CP supplement during the last trimester.
Remaining cows were not supplemented.
No other treatments were assigned to the heifer calves.
(Martin et al., 2007)

31. Effect of Late Gestation Supplementation on Performance of Heifer Progeny
Trait
PS Dams
NS Dams
P-value
Dam BCS at calving
5.2
4.6
.001
Birth wt, lbs
79.2
77.0
.25
Wean wt, lbs
466
455
.14
Adj. 205-d wt, lbs
497
480
.02
Prebreeding wt, lbs
607
585
.04
Preg check BW, lbs
880
849
.03
(Martin et al., 2007)

32. Effect of Late Gestation Supplementation on Performance of Heifer Progeny
Trait
PS Dams
NS Dams
P-value
Age at puberty, d
339
334
.70
Calved in first 21 d,% 77 49
.005
Overall pregnancy rate, % 93 80
.05
Calf birth wt, lbs 73
.94
Unassisted births, % 78 64
.24
(Martin et al., 2007)

33. Effect of Late Gestation Supplementation on Calf Performance
Item
PS Dams
NS Dams
P-value
Pre-calving BCS
5.1
4.7
.001
Pre-breeding BCS
4.9
.01
Weaning BCS
.21
Weaned calf %
98.5
93.6
.02
Pregnancy rate % 93 90
.46
(Stalker et al., 2006)

34. Effect of Late Gestation Supplementation on Calf Performance
Item
PS Dams
NS Dams
P-value
Calf birth wt, lbs
81.4
79.2
.29
Calf weaning wt, lbs
480
464
.02
Feedlot ADG, lbs
3.52
.89
Hot carcass wt, lbs
812
799
.23
Choice grade, %
96.4
85.4
.16
(Stalker et al., 2006)

35. Effect of Late Gestation Supplementation on Calf Performance
Similar experimental design to the two previous Nebraska studies.
Prepartum supplementation did not affect cow pregnancy rate.
Steers from supplemented dams had less sickness in the feedlot (1.5% vs 11.5%, P<.05)
Increased marbling and % choice grades (P<.05).
No effects on YG or carcass weights.
(Larson et al., 2009)

36. Late Gestation Supplementation and Cow BCS Effects on Cow & Calf Performance
Combination study of cow BCS at calving and late gestational supplementation.
Study design:
Cows were fed to achieve BCS 4 or 6 during second trimester.
During last trimester, half of the cows in each BCS group were supplemented while the other half was not.
After calving, cows were managed similarly.
(Bohnert et al., 2010)

37. Late Gestation Supplementation and Cow BCS Effects on Cow & Calf Performance
P-Value
Item
Supp
No Supp
4 vs 6
Supp or not
Initial BCS
4.32
4.39
5.67
5.75
<.001
.14
Calving BCS
4.57
4.33
5.51
5.18
Weaning BCS
4.74
4.61
5.30
5.19
.02
Calving %
86.7
93.3
100
.22
Weaning %
85.0
91.7
98.3
.16
Preg. Rate %
77.2
80.7
92.8
90.0
.005
.93
(Bohnert et al., 2010)

38. Late Gestation Supplementation and Cow BCS Effects on Cow & Calf Performance
P-Value
Item
Supp
No Supp
4 vs 6
Supp or not
Calf BW, lbs
85.8
84.7
93.7
88.4
.002
.05
Calf WW, lbs
414
394
422
409
.01
Growing ADG, lbs
1.39
1.32
1.41
1.30
.97
.26
Feedlot ADG, lbs
4.03
4.20
4.18
4.14
.84
.71
HCW, lbs
814
803
823
.79
.32
Choice, %
57.6
38.6
65.7
62.4
.13
.28
Yield Grade
3.4
3.3
.49
.86
Feedlot Health Costs
.58
4.59
2.72
11.98
(Bohnert et al., 2010)

39. Summary Points
Late gestational supplementation did not affect pregnancy rates of cows.
Some evidence that late gestation supplementation may:
Increase weaning weights
Improve replacement heifer fertility
Lower feedlot morbidity in steer calves
Improve quality grade

40. Sustained Nutrition™ Cow Nutrition Program
Provides consistent nutrition over the production cycle
Supplement intake varies based on:
Cow BCS and requirements
Forage quality and quantity
In multi-year evaluations, ranchers have reported:
Increased conception rates
Increased weaning weights
Less supplement usage and cost

41. Body Condition Score and Breeding Back
Steven E. Myers, Ph.D.